Underground and submersible junction bus connectors are widely used in electrical power distribution systems. One type of such connector is offered under the designation SWEETHEART® by Homac Mfg. Company of Ormond Beach, Fla., the assignee of the present invention. The SWEETHEART® connector is a cast or welded aluminum connector including an elongate bus portion and a series of tubular posts extending outwardly from the bus portion. The posts have an open upper end to receive one or more electrical conductors. A threaded bore is provided in the sidewall of the post to receive a fastener to secure the electrical conductor within the upper end of the post. U.S. Pat. No. 6,347,966, for example, discloses such a connector and a method for securing the posts to the bus portion.
An insulating coating is provided on the lower portion of the posts and bus of the connector. In addition, EPDM insulating boots or rockets may be used to provide waterproof seals to the insulating outer jacket of the wire or cable. These boots include an insulating tube having a lower end to be received onto the connector post. The upper end or end cap includes a series of progressively smaller diameter step or ring portions. An installer selects at which ring to cut the boot cap so that the resulting opening is properly sized for the diameter of electrical cable or wire to be received therein. U.S. Pat. No. 5,533,912 discloses a similar arrangement; however, the insulating boot with a stepped shape is positioned within a receiving port in an inverted configuration.
Unfortunately, water ingress, particularly where the boot is intended to seal against the jacket of the cable end, may result in corrosion and failure of the connector. When properly installed, such boots do not permit water ingress. Unfortunately, if improperly installed the seal provided by the boot may not be sufficient to keep water out. Accordingly, water may enter and degrade the electrical connection resulting in premature failure of the connector.
There is also a trend to require less highly skilled craftsman to install the connectors as a cost savings measure for utilities and their subcontractors. Instances of improper installation are more likely to occur as training and skill levels are reduced, and while at the same time greater production rates are required. For example, an improperly trained installer may cut the boot at a ring that is too large to correctly seal. Of course, the larger the ring, the less insertion force required to position the cable through the boot. Months or years after installation, water may penetrate the area of the seal and cause connector failure.
Other electrical connector insulator boots are described in U.S. Pat. No. 2,932,965 to Raila et al.; U.S. Pat. No. 3,740,692 to Filhaber; and U.S. Pat. No. 4,283,597 to Cooper, Jr. Unfortunately, these also may fail to provide proper sealing and/or accommodate different sized cable ends.